textproduct: Albany

WHAT HAS CHANGED

Lowered temperatures and dewpoints today and tonight as the high pressure system is directly overhead. Showers and thunderstorm chances largely remain on track from the previous forecast. After tomorrow night, the next best chance for rainfall looks to be mid to late next week.

KEY MESSAGES

1) Showers will become widespread across most of the area Saturday night into early Sunday. Localized downpours are expected and a few rumbles of thunder are also possible.

2) A cold front will bring isolated to scattered thunderstorms mainly areas north and west of the Capital Region Sunday afternoon and evening. Some storms could produce damaging winds.

3) It will be a mostly dry start to next week with slightly above normal temperatures with the next best chance for showers arriving mid to late week.

DISCUSSION

KEY MESSAGE 1...

Sunny and mostly clear skies will continue through the remainder of the afternoon and overnight as the high pressure remains overhead. This along with calming winds will make for favorable radiational cooling conditions dropping tonight's lows considerably cooler into the upper 30s in the Adirondacks and the upper 40s in the mid Hudson Valley. Patchy/areas of fog will occur in the typical sheltered valleys.

Tomorrow will remain dry, with increasing cloud cover as the high begins to depart towards the New England coast with a warmer southerly flow developing. This will bring a low pressure system up the coast from the south, coinciding with a short wave and surface cyclone near the NYC/Long Island area. Along with near normal to slightly above normal temperatures tomorrow, increased moisture will be advected into the region with ensemble models showing PWAT anomalies increasing to +1 to +2 STDEV Saturday afternoon to near the climatological 75th percentile for the region. Deep warm cloud layers are favorable for efficient warm rain processes but LCL-EL mean winds look fairly quicker at about 20-25 kt limiting concerns of repeated heavy showers over one location. CAMs have the timing of showers beginning around sunset and overspreading the region with more steadier showers after about 10 PM EDT and continuing through early Sunday morning before tapering off mid morning. Rainfall totals are expected to be in the 0.75" to 1.00" for areas south and east of the Capital Region and 0.25" to 0.50" for areas north and west of the Capital Region. Localized higher end amounts up to 1.50" are also possible especially in terrain enhanced areas. Probabilistic guidance has a widespread 60% to 70% chance for at least 0.25" however only a 20% to 30% chance for receiving 1.00" or greater. With currently dry antecedent soil conditions and FFG being 2.5" to 3.0"+, this looks to be more of a beneficial rainfall with a low chance for hydro concerns. However, ponding of water or nuisance flooding could occur in typical low lying, urban, or poor drainage areas. Instability is also lacking for any severe chances Saturday afternoon.

KEY MESSAGE 2...

After a brief break Sunday morning, isolated to widely scattered thunderstorms are expected to develop Sun afternoon ahead of a potent upper level short wave and associated surface cold front. Guidance indicating moderate instability developing, with 1000-1500 J/Kg SBCAPE across eastern NY, with < 1000 J/Kg in western New England. 0-6 km shear also increases to around 40-50 kt and moderate 700-500mb lapse rates range from 6-7 C/km. The CAPE/shear balance may result in organized linear storms, with some becoming strong to severe. Current CAMs show the best chance to be areas north and west of the Capital Region. With any thunderstorms that develop, damaging winds will be the primary threat and could blow around unsecured objects and down small tree limbs. Some uncertainty still exists in the timing of the cold front with a potential limiting factor being the amount of daylight left to help initiate storms when all these ingredients come together. The threat for storms will end Sun night, as a drier and cooler air mass builds in by Mon morning.

KEY MESSAGE 3...

High pressure begins to build back in on Monday with a dry start to next week. Temperatures look to be seasonable to sightly above normal with the next best chance for showers arriving mid to late week as the next frontal system approaches from the Great Lakes.

AVIATION /18Z FRIDAY THROUGH WEDNESDAY/

Through 18z Saturday...VFR conditions remain in place across all terminals this afternoon as high pressure continues to slide eastward across the region. Favored flying conditions will remain in place through the remainder of the day into tonight, though prime radiational cooling processes will likely lead to some shallow or even localized dense fog by tomorrow morning. TEMPO groups have been added accordingly for potential MVFR conditions at ALB and POU and IFR at GFL and PSF. Once fog burns off upon sunrise tomorrow morning, VFR conditions will swiftly return. Winds will remain breezy out of the northwest this afternoon with sustained speeds ranging from about 5-10 kt and gusts up to 20kt. However, with the loss of heating tonight, winds will go calm and become light and variable tomorrow.

Outlook...

Saturday Night: High Operational Impact. Definite SHRA...TSRA. Sunday: High Operational Impact. Likely SHRA...TSRA. Sunday Night: Moderate Operational Impact. Chance of SHRA. Monday: No Operational Impact. NO SIG WX. Monday Night: No Operational Impact. NO SIG WX. Tuesday: No Operational Impact. NO SIG WX. Tuesday Night: No Operational Impact. NO SIG WX. Wednesday: No Operational Impact. NO SIG WX.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...None. MA...None. VT...None.